Field of the Invention
The present invention relates to an image recognition device that recognizes a specific object image in an image, a method of controlling the same, and a storage medium, as well as an image pickup apparatus, and a display device.
Description of the Related Art
In recent years, some image pickup apparatuses are equipped with an object recognition function for recognizing a specific object image in images. The image pickup apparatuses equipped with the object recognition function are capable of performing focus control and exposure control preferentially on the recognized object image.
In the image pickup apparatus equipped with the object recognition function, first, an object image area including a specific object area is detected from image data obtained as a result of image pickup. Then, feature information for identifying the detected object image area as a recognition target is extracted. The extracted feature information is compared with feature information of registered target images registered in advance as dictionary data. Next, it is determined, based on the degree of similarity obtained by the comparison, to which registered target image the recognition target corresponds or whether or not there is no registered target image to which the recognition target corresponds.
For example, there has been proposed an image pickup apparatus in which when a specific object area is a human face, person recognition is performed by extracting feature information of a face area, and determining to which person an image of the face area corresponds (see Japanese Patent Laid-Open Publication No. 2003-187352).
By the way, in detecting an object area from image data obtained as a result of image pickup, if a plurality of object images exist in the image data, a plurality of object areas are detected as object image areas. In this case, the comparison of feature information for recognition of an object is performed by setting each of the object areas as a recognition target.
To this end, in the case where the plurality of object images exist in the image data obtained as the result of image pickup, if the number of recognition targets that can be set at a time is limited, it is necessary to select specific object areas from a plurality of object areas as recognition targets.
Further, the accuracy of object recognition, which is typified by person recognition, for identifying a human face is influenced by a facial expression and a face orientation in a face area, lighting conditions, etc. Therefore, when a state of a face area of a recognition target and a state of the corresponding face area in dictionary data are different, the accuracy of person recognition is sometimes lowered. In short, it is sometimes impossible to perform accurate person recognition, depending on the state of a face area as a recognition target.